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Full text of "Alaskan glacier studies of the National Geographic Society in the Yakutat Bay, Prince William Sound and lower Copper River regions"

MALASPINA GLACIER                                         53
ploughed up a ridge of blue clay in front of it ... thickly charged with sea shells of living species."
In neither 1905, 1906, nor 1909, did we make any observations on Seward Glacier or the Seward lobe of the Malaspina Glacier excepting to look out upon it from elevated points near the eastern margin of the Malaspina. Even such views, distant though they were, were sufficient to show that the Seward lobe had not in any one of these years felt the impulse of a forward thrust similar to that which swept down the Marvine lobe in 1906. From Blossom Island, in 1906, an area of crevassing was seen near the point where Seward Glacier emerges from its mountain valley which was thought to possibly represent the beginning of an advance, for one of the 1906 party, Mr. Alexander, who was on the Abruzzi Expedition in 1897, was sure that the crevassing was much greater the latter year in parts of the glacier sledged over by him nine years before. So far as could be seen in 1909 no great advance had taken place in the interval. The surface of the Seward lobe appeared to be as smooth as formerly, though near the mountains there is a very irregular ice surface which is probably normal, for photographs by the Duke of Abruzzi's party in 1897 also show crevassed ice in approximately this position.
It may be pointed out that it is quite possible for a large glacier, with many tributaries, to have more than one advance, with different degrees of intensity, as an outcome of earthquake shaking. The advance of one tributary, or of several combined, might cause slight advance, and later another greater advance might result from the thrust derived from a larger glacier or several tributaries. There is no proof that this has been the case in the Seward Glacier and it is merely stated as an interesting possibility, and in order to make it clear that a slight thrust may have occurred in 1906 and yet, after an interval of years, a still greater advance might begin.
MARVINE GLACIER
Stagnant in 1890. Russell describes Marvine Glacier within its mountain valley as partly covered with "interminable fields of angular debris,"1 with areas of "hard blue ice," some medial moraines, "broad areas covered with sand cones and glacier tables," but apparently, with no amount of crevassing such as would interfere with rapid packing over its surface.
The Marvine lobe of Malaspina Glacier seems to have also been inactive in 1890 and possibly at least as long before as 1874, as is suggested by the observation of the botanist Coville.2 In 1899 with a small party from the Harriman Expedition he spent several days on the eastern border of Malaspina Glacier about half way from Disenchantment Bay to Point Manby. Here the ice at the border of the Marvine lobe was covered with a tTim layer of soil which supported vegetation. There were no spruces growing on the ice but the oldest alder bushes were perhaps 8 feet high and 25 years old.
Little Changed in 1905. On August 22nd, 1905, the junior author climbed up from Hayden Glacier and looked out upon the Marvine and Malaspina Glaciers, with field glasses, from an elevation of 1585 feet on the Floral Hills. At that time the valley portion of Marvine Glacier and a broad belt along the eastern margin of the Marvine lobe
i Nat. Geog. Mag., Vol. m, 1891, pp. 12&-128 and PI. 17. > Coville, F. V., Personal communication.